We previously showed microRNAs (miRNAs) in plasma are potential biomarkers for colorectal cancer detection. Here, we aimed to develop specific blood-based miRNA assay for breast cancer detection.
...TaqMan-based miRNA profiling was performed in tumor, adjacent non-tumor, corresponding plasma from breast cancer patients, and plasma from matched healthy controls. All putative markers identified were verified in a training set of breast cancer patients. Selected markers were validated in a case-control cohort of 170 breast cancer patients, 100 controls, and 95 other types of cancers and then blindly validated in an independent set of 70 breast cancer patients and 50 healthy controls. Profiling results showed 8 miRNAs were concordantly up-regulated and 1 miRNA was concordantly down-regulated in both plasma and tumor tissue of breast cancer patients. Of the 8 up-regulated miRNAs, only 3 were significantly elevated (p<0.0001) before surgery and reduced after surgery in the training set. Results from the validation cohort showed that a combination of miR-145 and miR-451 was the best biomarker (p<0.0001) in discriminating breast cancer from healthy controls and all other types of cancers. In the blind validation, these plasma markers yielded Receiver Operating Characteristic (ROC) curve area of 0.931. The positive predictive value was 88% and the negative predictive value was 92%. Altered levels of these miRNAs in plasma have been detected not only in advanced stages but also early stages of tumors. The positive predictive value for ductal carcinoma in situ (DCIS) cases was 96%.
These results suggested that these circulating miRNAs could be a potential specific biomarker for breast cancer screening.
A single-step method was developed for biodiesel production from unrefined or waste oils using a series of heterogeneous zinc and lanthanum mixed oxides. Effects of metal oxide molar ratio, free ...fatty acids (FFA) and water content in feedstock, molar ratio of methanol and oil, and reaction temperature on the yield of biodiesel were investigated. A strong interaction between Zn and La species was observed with enhanced catalyst activities. Lanthanum promoted zinc oxide distribution, and increased the surface acid and base sites. The catalyst with 3:1 ratio of zinc to lanthanum was found to simultaneously catalyze the oil transesterification and fatty acid esterification reactions, while minimizing oil and biodiesel hydrolysis. A reaction temperature window of 170-220 deg C was found for the biodiesel formation. A high yield (96%) of fatty acid methyl esters (FAME) was obtained within 3 h even using unrefined or waste oils.
Lithium Sulfur (Li/S) chemistries are amongst the most promising next-generation battery technologies due to their high theoretical energy density. However, the detrimental effects of their ...intermediate byproducts, polysulfides (PS), have to be resolved to realize these theoretical performance limits. Confined approaches on using porous carbons to entrap PS have yielded limited success. In this study, we deviate from the prevalent approach by introducing catalysis concept in Li/S battery configuration. Engineered current collectors were found to be catalytically active towards PS, thereby eliminating the need for carbon matrix and their processing obligatory binders, additives and solvents. We reveal substantial enhancement in electrochemical performance and corroborate our findings using a detailed experimental parametric study involving variation of several kinetic parameters such as surface area, temperature, current rate and concentration of PS. The resultant novel battery configuration delivered a discharge capacity of 700 mAh g(-1) with the two dimensional (2D) planar Ni current collectors and an enhancement in the capacity up to 900 mAh g(-1) has been realized using the engineered three dimensional (3D) current collectors. The battery capacity has been tested for stability over 100 cycles of charge-discharge.
Production of biofuel from algae is dependent on the microalgal biomass production rate and lipid content. Both biomass production and lipid accumulation are limited by several factors, of which ...nutrients play a key role. In this research, the marine microalgae
Dunaliella tertiolecta was used as a model organism and a profile of its nutritional requirements was determined. Inorganic phosphate
PO
4
3
-
and trace elements: cobalt (Co
2+), iron (Fe
3+), molybdenum (Mo
2+) and manganese (Mn
2+) were identified as required for algae optimum growth. Inorganic nitrogen in the form of nitrate
NO
3
-
instead of ammonium (NH
4
+) was required for maximal biomass production. Lipids accumulated under nitrogen starvation growth condition and this was time-dependent. Results of this research can be applied to maximize production of microalgal lipids in optimally designed photobioreactors.
•Supported bimetallic oxide precursors were prepared by impregnation method.•Carbides of the catalysts were formed by temperature-programmed reduction (TPR).•NiMoC/Al-SBA-15 shows the highest surface ...area and largest pore volume.•NiMoC/Al-SBA-15 gave the highest yield to diesel range hydrocarbons.
As an alternative to conventional sulfide catalysts, NiMo carbide catalysts were prepared by impregnation method and studied for the hydrotreating of soybean oil to produce hydrocarbons in the gasoline to diesel range. The effect of the catalyst supports on activity and selectivity was investigated by using three different types of materials: mesoporous material (Al-SBA-15), alumina (γ-Al2O3) and zeolites (ZSM-5, Zeolite β and USY). The structural characterization of the catalysts was performed using XRD, BET and TEM. Catalytic tests were carried out in a bench scale flow reactor at 400°C and 650psi. The results showed that the Al-SBA-15 supported catalyst has the highest surface area of 711.5m2g−1 and largest pore volume of 0.71cm3g−1. Among the five catalysts, hydrotreating on NiMoC/Al-SBA-15 gave the highest yield of organic liquid product (96%) and highest selectivity (97%) to hydrocarbons in the boiling range of the diesel fraction. For the three zeolite-supported catalysts, hydrotreating of soybean oil produced more hydrocarbon products in the boiling range of green gasoline (about 15–40%).
The formation of precipitates in biodiesel blends may have serious implications for diesel engine fuel delivery systems. Precipitates were observed in Soybean oil (SBO-), cottonseed oil (CSO-), and ...poultry fat (PF-) based biodiesel blends after storage at 4
°C. CSO- and PF-based biodiesel had a lower mass of precipitates observed than the SBO-based. Moreover, different rates of precipitate formation were observed for the B20 versus the B100. These suggested that the formation of precipitate during cold temperature storage was dependent on the feedstock and blend concentration. The solvency effects of biodiesel blends were more pronounced at low temperature than at room temperature leading to a higher amount of precipitates formed. Fourier transform infrared (FTIR) spectra, and gas chromatography-flame ionization detector (GC-FID) chromatograms indicated that steryl glucosides are the major cause of precipitate formation in SBO-based biodiesel; while for PF-based biodiesel, the precipitates are due to mono-glycerides. However, the precipitates from CSO-based biodiesel are due to both steryl glucosides and mono-glycerides.
•Hydrothermal decarboxylation of oleic acid over bimetallic Ni carbide catalysts was studied.•Supercritical conditions promote hydrogenation–decarboxylation reactions of oleic acid.•The catalysts can ...utilize aqueous phase reforming of glycerol for in situ H2 production.•Adding glycerol increased the conversion of oleic acid and selectivity of heptadecane.•NiWC/Al-SBA-15 exhibited high ability to produce heptadecane from triglycerides.
Several Ni-based transition metal carbide catalysts supported on Al-SBA-15 were studied for the hydrothermal decarboxylation of oleic acid and soybean oil to produce diesel range hydrocarbons with no added H2. The effect of pre-reduction, sub-critical, and super-critical water conditions on the catalyst activity and selectivity was investigated. Both the conversion of oleic acid and selectivity of decarboxylation products under super-critical conditions for each catalyst were about two times greater than at sub-critical conditions. In addition, the potential of these catalysts for utilizing aqueous phase reforming (APR) of glycerol for in situ H2 production to meet process demands was demonstrated. The performance of the catalysts increases with the addition of glycerol, especially for the NiWC/Al-SBA-15 catalyst. With the addition of glycerol, the NiWC/Al-SBA-15 catalyst showed greater conversion of oleic acid and selectivity to heptadecane; however, most of the oleic acid was hydrogenated to produce stearic acid. The highest conversion of oleic acid and selectivity for heptadecane was 97.3% and 5.2%, respectively. Furthermore, the NiWC/Al-SBA-15 catalyst exhibited good potential for hydrolyzing triglycerides (soybean oil) to produce fatty acids and glycerol, and then generating H2in situ from the APR of the glycerol produced. A complete conversion of soybean oil and hydrogenation of produced oleic acid were obtained over the NiWC/Al-SBA-15 at super-critical conditions.
Zirconia supported metal oxides catalyst (ZnO–TiO2–Nd2O3/ZrO2) has been developed for biodiesel production with low grade oil containing a lot of free fatty acid. The catalyst has been tested in a ...packed bed reactor at reaction temperature 195°C and pressure 300psi for 6months. The catalyst is enable to produce biodiesel with low grade oil in an environmentally-friendly way. Display omitted
► Development of a very active pellet type of ZrO2 catalyst for biodiesel production. ► Durable catalyst by using supported mixed metal oxides on ZrO2. ► Attaining 99% FAME yield by using two-stages packed bed reactors. ► Dependency of the catalytic activity on the supported metal oxides.
A new class of zirconia supported mixed metal oxides (ZnO–TiO2–Nd2O3/ZrO2 and ZnO–SiO2–Yb2O3/ZrO2) has demonstrated the ability to convert low quality, high free fatty acid (FFA) bio-oils into biodiesel. Pelletized catalysts of ZrO2 supported metal oxides were prepared via a sol–gel process and tested in continuous flow packed bed reactors for up to 6months. In a single pass, while operating at mild to moderate reaction conditions, 195°C and 300psi, these catalysts can perform simultaneous esterification and transesterification reactions on feedstock of 33% FFA and 67% soybean oil to achieve FAME yields higher than 90%. Catalytic activity of the ZrO2 supported metal oxide catalysts was highly dependent on the metal oxide composition. These heterogeneous catalysts will enable biodiesel manufacturers to avoid problems inherent in homogeneous processes, such as separation and washing, corrosive conditions, and excessive methanol usage.
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